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Some of the World's Biggest Lakes Are Drying Up

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Re: Some of the World's Biggest Lakes Are Drying Up

#31

Post by anvandare »

joncrane wrote: post #7

Where is the water going, though? Isn't water a zero-sum game in the sense that Earth is a closed system?

Just like energy and entropy, it becomes harder to harvest efficiently. There's still just as much water, it's just not easily accessible. The difference between the water in your glass and the water in the cubic foot of earth after you spill your glass on it. You can't drink from the latter.

The water cycle does the collection for us (lakes, rivers, aquifers) but we're draining them faster than they can recharge, particularly problematic are the melting glaciers (in the Himalayas) and the aquifers:

https://en.wikipedia.org/wiki/Aral_Sea

https://www.washingtonpost.com/news/energy-environment/wp/20...

http://lcluc.umd.edu/hotspot/glacial-retreat-himalayas

https://www.nasa.gov/feature/goddard/2017/11-percent-of-disa...

https://www.jpl.nasa.gov/news/news.php?feature=4626

Re: Some of the World's Biggest Lakes Are Drying Up

#32

Post by Someone »

echevil wrote: post #25
joncrane wrote: post #7

Where is the water going, though? Isn't water a zero-sum game in the sense that Earth is a closed system?

See levels are rising

Yes, but it is only a small contribution. Most of Earth’s liquid water already is in oceans. https://en.wikipedia.org/wiki/Water_distribution_on_Earth#Di...:

  - Oceans              96,5%
  - Antarctic ice sheet  1,56%
  - Lakes                0,013%
https://en.wikipedia.org/wiki/Antarctic_ice_sheet:

“Approximately 61 percent of all fresh water on the Earth is held in the Antarctic ice sheet, an amount equivalent to about 58 m of sea-level rise.”

⇒ completely emptying all lakes in the world into the sea would rise sea levels by half a meter or so.

Re: Some of the World's Biggest Lakes Are Drying Up

#33

Post by mseebach »

libertine wrote: post #17
narag wrote: post #13

Earlier quoted context omitted.

Spain mainland is separated from Africa by a mere 14 km strait, so no wonder temperature is similar, not talking about Canary Islands that are like a thousand km further to the south. Southwest mainland is becoming a desert indeed, but that's nothing new. Most classic spagetti westerns were filmed there. It's Sahara crossing the sea and a good thing for "plastic sea" (greenhouses). Almería provides several vegetables…

Uh, neither Spain or Portugal has ever had the same climate has the north of Africa - not at least in the recorded history. Here's an example of the 27th of February: http://images.meteociel.fr/im/8481/temp_eur2_crn3.png

Climate != weather.

I'm sure you can find plenty of examples in recorded history when those areas had roughly the same weather.

Re: Some of the World's Biggest Lakes Are Drying Up

#34

Post by candiodari »

IntronExon wrote: post #23
candiodari wrote: post #21

Earlier quoted context omitted.

... in the sense that the costs can just be imposed on people who can't defend themselves. And at that point, cheaper, more expensive ... ah what's the difference ? I mean, that's a slightly different wording of the argument you're making. In other words: this needs an economically viable solution. We need an absurdly cheap way to refill the lakes. Conservation isn't that, but everybody proposing it knows where the c…

I’m curious who do you think is suffering now as a result of drought and diminishing ecological resources? Who is going to suffer through famine and drought? Your point is valid, but only insofar as people who can’t defend themselves always suffer. Every course of action hurts the group you’re concerned about, but the most likely to succeed and least damaging is conservation.

Well the problem is the large cities taking up all capacity in the rivers and the people who suffer are the people on the coastlines of those lakes.

The capacity in the rivers, by and large, is not taken up by people on those coastlines.

And conservation, I bet, "somehow" misses this reality. So it attempts to protect things like tourism income at the further expense of the victims. But nobody, absolutely nobody is talking about denying cities the water they depend on (which will dry up anyway, but not for a while yet ...).

You see the problem is not global warming. The problem is those cities and countries that take away the resources these lakes depend on. If you calculate the resulting change in precipitation from the 1 degree or so of temperature change we've seen, that's not what's making the difference here. The difference is those cities.

But of course, we "need to conserve". And what do we mean by that, exactly ? Why, the victims of it, the people living on that coastline, those need to be forced to abandon their lives, because otherwise the tourism that the rest of country profits from (but not so much those people), could get hit ... first a bit, then a lot. That's what we mean by conservation.

Re: Some of the World's Biggest Lakes Are Drying Up

#35

Post by libertine »

mseebach wrote: post #33
libertine wrote: post #17

Earlier quoted context omitted.

Uh, neither Spain or Portugal has ever had the same climate has the north of Africa - not at least in the recorded history. Here's an example of the 27th of February: http://images.meteociel.fr/im/8481/temp_eur2_crn3.png

Climate != weather. I'm sure you can find plenty of examples in recorded history when those areas had roughly the same weather.

I know the difference - but when a pattern of similar weather is noticed in the past 5-10 years, it's more than just weather, I believe it's climate.

What worries the most isn't how warm or cold it guets, it's precisely how dry it is.

Re: Some of the World's Biggest Lakes Are Drying Up

#36

Post by tpm »

narag wrote: post #13
libertine wrote: post #3

You don't need to go to South America, Asia or middle East - it's happening in Europe and no one seems to notice. Look at Portugal and Spain, it's becoming a desert - the day of the cold wave the south of Portugal and Spain had the same temperatures of some country's in Africa.

Spain mainland is separated from Africa by a mere 14 km strait, so no wonder temperature is similar, not talking about Canary Islands that are like a thousand km further to the south. Southwest mainland is becoming a desert indeed, but that's nothing new. Most classic spagetti westerns were filmed there. It's Sahara crossing the sea and a good thing for "plastic sea" (greenhouses). Almería provides several vegetables…

Not only neighbours, a big part of Eastern Europe in winter too. But the greenhouses also need a lot of water and that is getting scarce there, or not?

Re: Some of the World's Biggest Lakes Are Drying Up

#37

Post by DennisP »

bilbo0s wrote: post #28
lisper wrote: post #26

Earlier quoted context omitted.

> China has invested billions in constructing mammoth aqueducts to do just this This is also the reason they invaded Tibet.

Maybe someone gave you water as a newly made up excuse for China taking Tibet? But make no mistake about it, on October 7, 1950, the Chinese were not thinking about water. I'm fairly certain most historians would agree on that point.

Here are two comments on r/askhistorians saying water was one of the reasons [1], along with natural resources in general [2].

Of course that's not the only reason; other answers make clear there were a lot of factors. Now though, Tibetan water is a huge issue, including for other countries downstream of Tibet including India and Pakistan [3]. There are no water treaties between these countries; China has been building a lot of dams and is planning a massive 600-mile pipeline to divert Tibetan water that would otherwise go to India [4].

Tibet is the third largest repository of fresh water after the two poles [5].

[1] https://www.reddit.com/r/AskHistorians/comments/35fuz5/leavi...

[2] https://www.reddit.com/r/AskHistorians/comments/2giaje/was_t...

[3] https://www.equaltimes.org/china-s-water-grab-in-tibet-risks

[4] https://qz.com/1114843/chinas-grand-plan-for-the-brahmaputra...

[5] https://www.theglobalist.com/tibet-and-21st-century-water-wa...

Re: Some of the World's Biggest Lakes Are Drying Up

#38

Post by mseebach »

libertine wrote: post #35
mseebach wrote: post #33

Earlier quoted context omitted.

Climate != weather. I'm sure you can find plenty of examples in recorded history when those areas had roughly the same weather.

I know the difference - but when a pattern of similar weather is noticed in the past 5-10 years, it's more than just weather, I believe it's climate. What worries the most isn't how warm or cold it guets, it's precisely how dry it is.

No, you don't know the difference when you talk about climates and then link to the weather for a single day as supporting evidence.

Re: Some of the World's Biggest Lakes Are Drying Up

#39

Post by DennisP »

teslabox wrote: post #8

How much of the missing water is actually due to higher temperatures, and how much is due to people siphoning water from the aquifers that feed the lake? This article mostly focuses on "climate change" hysterics, but also acknowledges the siphoning problem. A HN comment [0] linked to a TucsonWeekly [1] piece about how Tucson used to be an oasis. Similarly, the Salt River used to run year-round through Phoenix. Las Ve…

Maybe it's all of the above, much like ocean life is on the decline for multiple reasons including excess heat and acidification from excess CO2, but also including overfishing, pollution, and algae blooms due to fertilizer runoff.

Re: Some of the World's Biggest Lakes Are Drying Up

#40

Post by graeme »

eloff wrote: post #24
siculars wrote: post #22

Call me naive but I read the article as consequences of acute human expansion. Virtually every example was followed by explanations along the lines of “man made canals, irrigation, mining...” I really think technology and better civil planning will be the way to fix these problems. Technology will cause the cost of renewable energy to trend towards zero while better civil planning will apply that energy to pump water…

China has invested billions in constructing mammoth aqueducts to do just this: https://en.wikipedia.org/wiki/South%E2%80%93North_Water_Tran... https://www.gokunming.com/en/blog/item/4038/china_considerin... Meanwhile in Western Canada, we steadfastly refuse to sell water into the US, despite all of our fresh water running into the Pacific Ocean anyway...

In Canada there exists a widespread belief that if you start selling water, you have to sell it.

I am not sure this is correct, but it is widespread, and probably affects willingness to sell anything.

http://www.cbc.ca/radio/the180/more-on-nafta-and-water-parti...

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